inventory_source_item and cataloginventory_stock_item data is not same? which table to used for stock now. Please explain. Thanks so much
The answer is 'yes and no' :)
If you are using the enabled MSI functionalities with the default stock and default source only, then, when you update a product's qty, the same qty will be displayed on both
However, when you have different stocks with sources assigned to your product (out of which one is the default source from the default stock), the
inventory_source_item stores an entry for each of the sources and
cataloginventory_stock_item stores only the value on the 'default source' from Magento OOTB, any other custom source will be ignored here.
This means that if you have a product which is not assigned on Magento OOTB default stock with its default source, then qty in
cataloginventory_stock_item for that product will be 0.